Hyperspectral imaging (HSI) is an emerging imaging modality for medical applications, especially in disease diagnosis and image-guided surgery. HSI acquires a three-dimensional dataset called hypercube, with two spatial dimensions and one spectral dimension. Spatially resolved spectral imaging obtained by HSI provides diagnostic information about the tissue physiology, morphology, and composition. This review paper presents an overview of the literature on medical hyperspectral imaging technology and its applications. The aim of the survey is threefold: an introduction for those new to the field, an overview for those working in the field, and a reference for those searching for literature on a specific application.

https://www.spiedigitallibrary.org/journals/journal-of-biomedical-optics/volume-19/issue-1/010901/Medical-hyperspectral-imaging-a-review/10.1117/1.JBO.19.1.010901.pdf

Medical hyperspectral imaging: a review

Here, we define dynamic reciprocity (DR) as an ongoing, bidirectional interaction among cells and their surrounding microenvironment. In this review, we posit that DR is especially meaningful during wound healing as the DR-driven biochemical, biophysical, and cellular responses to injury play pivotal roles in regulating tissue regenerative responses. Such cell-extracellular matrix interactions not only guide and regulate cellular morphology, but also cellular differentiation, migration, proliferation, and survival during tissue development, including, e.g., embryogenesis, angiogenesis, as well as during pathologic processes including cancer, diabetes, hypertension, and chronic wound healing. Herein, we examine DR within the wound microenvironment while considering specific examples across acute and chronic wound healing. This review also considers how a number of hypotheses that attempt to explain chronic wound pathophysiology may be understood within the DR framework. The implications of applying the principles of DR to optimize wound care practice and future development of innovative wound healing therapeutics are also briefly considered.

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Dynamic reciprocity in the wound microenvironment

A number of improvements are provided relating to computer aided surgery utilizing an on tool tracking system. The various improvements relate generally to both the methods used during computer aided surgery and the devices used during such procedures. Other improvements relate to the structure of the tools used during a procedure and how the tools can be controlled using the OTT device. Still other improvements relate to methods of providing feedback during a procedure to improve either the efficiency or quality, or both, for a procedure including the rate of and type of data processed depending upon a CAS mode.

On-board tool tracking system and methods of computer assisted surgery

Ischemia complicates wound closure. Here, we are unique in presenting a murine ischemic wound model that is based on bipedicle flap approach. Using this model of ischemic wounds we have sought to elucidate how microRNAs may be implicated in limiting wound re-epithelialization under hypoxia, a major component of ischemia. Ischemia, evaluated by laser Doppler as well as hyperspectral imaging, limited blood flow and lowered tissue oxygen saturation. EPR oximetry demonstrated that the ischemic wound tissue had pO(2) <10 mm Hg. Ischemic wounds suffered from compromised macrophage recruitment and delayed wound epithelialization. Specifically, epithelial proliferation, as determined by Ki67 staining, was compromised. In vivo imaging showed massive hypoxia inducible factor-1alpha (HIF-1alpha) stabilization in ischemic wounds, where HIF-1alpha induced miR-210 expression that, in turn, silenced its target E2F3, which was markedly down-regulated in the wound-edge tissue of ischemic wounds. E2F3 was recognized as a key facilitator of cell proliferation. In keratinocytes, knock-down of E2F3 limited cell proliferation. Forced stabilization of HIF-1alpha using Ad-VP16- HIF-1alpha under normoxic conditions up-regulated miR-210 expression, down-regulated E2F3, and limited cell proliferation. Studies using cellular delivery of miR-210 antagomir and mimic demonstrated a key role of miR-210 in limiting keratinocyte proliferation. In summary, these results are unique in presenting evidence demonstrating that the hypoxia component of ischemia may limit wound re-epithelialization by stabilizing HIF-1alpha, which induces miR-210 expression, resulting in the down-regulation of the cell-cycle regulatory protein E2F3.

Hypoxia inducible microRNA 210 attenuates keratinocyte proliferation and impairs closure in a murine model of ischemic wounds

Hyperspectral imaging (HSI) is an emerging modality for various medical applications. Its spectroscopic data might be able to be used to noninvasively detect cancer. Quantitative analysis is often necessary in order to differentiate healthy from diseased tissue. We propose the use of an advanced image processing and classification method in order to analyze hyperspectral image data for prostate cancer detection. The spectral signatures were extracted and evaluated in both cancerous and normal tissue. Least squares support vector machines were developed and evaluated for classifying hyperspectral data in order to enhance the detection of cancer tissue. This method was used to detect prostate cancer in tumor-bearing mice and on pathology slides. Spatially resolved images were created to highlight the differences of the reflectance properties of cancer versus those of normal tissue. Preliminary results with 11 mice showed that the sensitivity and specificity of the hyperspectral image classification method are 92.8% to 2.0% and 96.9% to 1.3%, respectively. Therefore, this imaging method may be able to help physicians to dissect malignant regions with a safe margin and to evaluate the tumor bed after resection. This pilot study may lead to advances in the optical diagnosis of prostate cancer using HSI technology.

/pdf/hyperspectral-imaging-and-quantitative-analysis-for-prostate-5c123ydxgj.pdf

Hyperspectral imaging and quantitative analysis for prostate cancer detection.

OBJECTIVE — Foot ulceration is a serious complication of diabetes, and new techniques that can predict wound healing may prove very helpful. We tested the ability of medical hyperspectral technology (HT), a novel diagnostic scanning technique that can quantify tissue oxy- and deoxyhemoglobin to predict diabetic foot ulcer healing. RESEARCH DESIGN AND METHODS — Ten type 1 diabetic patients with 21 foot ulcer sites, 13 type 1 diabetic patients without ulcers, and 14 nondiabetic control subjects were seen up to 4 times over a 6-month period. HT measurements of oxyhemoglobin (HT-oxy) and deoxyhemoglobin (HT-deoxy) were performed at or near the ulcer area and on the upper and lower extremity distant from the ulcer. An HT healing index for each site was calculated from the HT-oxy and -deoxy values. RESULTS — Hyperspectral tissue oxygenation measurements observed changes in tissue immediately surrounding the ulcer when comparing ulcers that heal and ulcers that do not heal (P 0.001). The sensitivity, specificity, and positive and negative predictive values of the HT index for predicting healing were 93, 86, 93, and 86%, respectively, when evaluated on images taken at the first visit. Changes in HT-oxy among the three risk groups were noted for the metatarsal area of the foot (P 0.05) and the palm (P 0.01). Changes in HT-deoxy and the HT healing index were noted for the palm only (P 0.05 and P 0.01, respectively). CONCLUSIONS — HT has the capability to identify microvascular abnormalities and tissue oxygenation in the diabetic foot and predict ulcer healing. HT can assist in the management of foot ulceration.

https://care.diabetesjournals.org/content/diacare/30/4/903.full.pdf

The Use of Medical Hyperspectral Technology to Evaluate Microcirculatory Changes in Diabetic Foot Ulcers and to Predict Clinical Outcomes

The present invention provides a hyperspectral imaging system which demonstrates changes in tissue oxygen delivery, extraction and saturation during shock and resuscitation including an imaging apparatus for performing real-time or near real­time assessment and monitoring of shock, including hemorrhagic, hypovolemic, cardiogenic, neurogenic, septic or burn shock. The information provided by the hyperspectral measurement can deliver physiologic measurements that support early detection of shock and also provide information about likely outcomes.

Hyperspectral/multispectral imaging in determination, assessment and monitoring of systemic physiology and shock

Apparatus and methods for hyperspectral imaging analysis that assists in real and near-real time assessment of biological tissue condition, viability, and type, and monitoring the above over time. Embodiments of the invention are particularly useful in surgery, clinical procedures, tissue assessment, diagnostic procedures, health monitoring, and medical evaluations, especially in the detection and treatment of cancer.

Medical hyperspectral imaging for evaluation of tissue and tumor

Disclosed is a bioimpedance measurement system: A stabilized high frequency current generator is connected to PadSet electrodes via a Patient Cable. Electrodes are connected to an adaptive circuit that conditions the resulting voltage signal and converts it to digital form. Firmware performs signal acquisition and relays data to the device.

Advanced respiratory monitor and system

L'invention concerne un appareil et des procedes destines a analyser l'imagerie en hyperespace spectral qui assiste l'evaluation de la condition, de la viabilite et du type de tissu biologique en temps reel et en temps quasi reel, et qui les regulent dans le temps. Certains modes de realisation de cette invention sont particulierement utiles dans la chirurgie, des procedures cliniques, l'evaluation de tissus, des procedures de diagnostic, le controle de la sante, et dans les evaluations medicales, notamment la detection et le traitement du cancer.

Alexander Panasyuk

Papers

The Use of Medical Hyperspectral Technology to Evaluate Microcirculatory Changes in Diabetic Foot Ulcers and to Predict Clinical Outcomes

Hyperspectral/multispectral imaging in determination, assessment and monitoring of systemic physiology and shock

Medical hyperspectral imaging for evaluation of tissue and tumor

Advanced respiratory monitor and system

Imagerie medicale en hyperespace spectral destinee a l'evaluation de tissus et de tumeurs